Level skip:
Press [Ctrl] + [Alt] + [Shift] + [End] during game play.
More money:
Note: This procedure involves editing a game file; create a backup copy of
the file before proceeding. Use a text editor to edit the "user.cfg" file in
the game directory. Change the value after the "cash_bonus" entry to
increase the amount of additional money available at the start of each level.
Easy no kill missions:
Note: This procedure involves editing a game file; create a backup copy of
the file before proceeding. Use a text editor to edit the "user.cfg" file in
the game directory. Enter "cheats_active" on a new line, then enter
"nokillgoalcheat" on the next line. You will now be able to pass the
objectives in any mission that requires you not to kill anyone.
Glitch: More money:
Save the game immediately before completing a mission. Complete the mission
as usual, and save the game in a different save position. Reload save that
was made before the mission was completed. Complete the mission again. The
statistics screen will combine the money from both missions. Repeat this to
earn as much as needed.